Privacy Policy

1. Information stored on your device

TENGlish Coach stores saved expressions, sentences and check results, voice preference, Assistant history, practice activity, and other learning evidence locally on your device. Learning does not require an account. Signing in does not upload or synchronize your learning collection. Separately enabled AI features may process the limited learning information described below.

Optional Sign in with Apple and local profile

Versions with account access use Apple's native authorization. Profile-enabled versions request the name and email that you choose to share with Apple; a private relay email may be used. We never request your Apple password. Apple does not supply an account photograph. You may choose a profile photo with the system photo picker and edit your display name. The app stores these profile details on this device, separately for each signed-in Apple user; the photo is not uploaded to our servers or OpenAI, and profile files are excluded from device backups.

The app temporarily sends Apple's identity token (which may contain an email claim) and one-time authorization code to our Global account service, which verifies the identity and exchanges the code with Apple. The service stores a hashed Apple user identifier, a random account identifier, an encrypted Apple refresh token, hashed session credentials, and account/session timestamps, not your profile name, email or photo. The app keeps its session credential and Apple user identifier in the device Keychain. These credentials are not sent to OpenAI.

Login sessions are valid for up to 30 days. Account records remain until you delete the account. In Account, you can sign out or delete your server account and login sessions; account deletion also requests revocation of Apple's authorization and removes that account's local profile. Signing out hides the profile but preserves it locally for your next sign-in. If deletion fails, the app reports the failure and you can retry or contact support. Account deletion preserves your separate local learning collection; uninstalling the app is not a request to delete the server account.

2. AI Assistant

The Assistant is optional. When you submit a request, TENGlish Coach sends the text you enter and up to five relevant learning records through our Global gateway to OpenAI so it can generate the requested learning feedback. Relevant records may include a saved expression, a lesson title, a check result, or a note you chose to create.

The app also sends a pseudonymous installation identifier and Apple App Attest integrity information to authenticate the installation, prevent replay, apply usage limits, and protect the service from abuse. Our gateway may process a hashed form of the installation identifier and IP address for these security and rate-limiting purposes.

Requests are configured not to store generated responses through the OpenAI API. OpenAI processes requests under its applicable business and privacy terms. Do not enter confidential, financial, medical, or other sensitive personal information in the Assistant. Read the AI feature disclosure for the product boundary and limitations.

3. Content and technical services

TENGlish Coach requests approved daily lessons, city artwork, and content updates from our Global content service. Like most online services, our servers and infrastructure providers may receive technical network information such as IP address, request time, response status, and device or app information needed to deliver, secure, and troubleshoot the service.

The app identifies source and licensing information for reviewed public materials. If you choose to open an external source or attribution link, that website handles the visit under its own privacy policy.

Optional AI shortlisting

In versions with Library shortlisting, only after you confirm the disclosure, your learning goal and up to 30 displayed English terms and their English meanings are sent through the Global gateway to OpenAI. This request excludes source articles, personal notes, account details and login credentials. App Attest and usage protections also apply. OpenAI response storage is disabled; the full library remains available without shortlisting.

Optional language support and next-day practice

In versions with language support, after your permission, opening a learning item can send its English word or phrase, part of speech, meaning, context and examples through the Global gateway to OpenAI for an easier English explanation. Chinese translations are requested when you reveal Chinese support, and cover the displayed meanings, sentences or questions. These requests exclude your name, email, photo and personal notes. Explanations and translations are cached on your device.

Next-day adaptation requires a separate opt-in. When the app is opened or returns to the foreground on a later day, it can send your chosen starting point, up to 60 reviewed learning candidates and up to 500 study outcomes from the preceding 60 completed days to OpenAI through the Global gateway. Outcomes describe opens, listens, saves, recall attempts and understanding-check results, rather than personal notes or account details. The result recommends a practice order, with spaced review and gradual difficulty changes. It does not approve or publish content, impose a daily quota, or assess a certified CEFR level.

For both features, App Attest and usage protections apply. The gateway does not persist the submitted study text, study outcomes or generated assistance; OpenAI response storage is disabled. You can disable future requests in Settings. Existing cached explanations, translations and the full learning library remain available.

4. Information we do not collect

• No microphone recordings, speaking samples, contacts, precise location or videos. A profile photo you select stays on your device; we do not request access to your entire photo library.
• No advertising identifier, cross-app tracking, or sale of personal information.
• No Apple password, payment information, subscription history, or cloud address book.

5. Retention and protection

Local learning data remains on your device until you remove it through the app or delete the app. Service-side technical and security records are retained only for the period reasonably needed to operate, secure, investigate abuse of, and meet legal obligations for the service. We use transport encryption and region-specific service boundaries, but no online system can be guaranteed completely secure.

6. Your choices

• You can use Learn, Library, reviewed context, American and British read-aloud, checks, and your saved collection without enabling AI features.
• You can manage your saved learning collection in the app, or delete the app to remove its local data.
• You can leave Chinese support hidden, turn off language assistance and next-day adaptation in Settings, and avoid opening external source links.
• You may contact us to ask a privacy question or request action concerning service-side information that can reasonably be identified.

7. Children

TENGlish Coach is a general English-learning product and is not directed to children under 13. We do not knowingly collect personal information from a child under 13. If you believe a child has provided such information, contact us.

8. International processing and changes

The Global edition uses international infrastructure and OpenAI rather than the separate China service path. Information may be processed in the United States or other locations where our service providers operate, subject to applicable safeguards. We may update this policy as the product or law changes; the effective date above identifies the current version.

9. Contact

Cleanteng Flight, LLC
Email: evan@cleantengflight.com